Dyes have been widely used in a variety of technical fields so far. In the field of photoelectric conversion devices such as solar cells, for instance, dyes having photosensitizing properties have been used in dye-sensitized photoelectric conversion devices. Dye-sensitized photoelectric conversion devices are expected to theoretically achieve high efficiency and be produced at lower cost than conventional photoelectric conversion devices employing silicon semiconductors. Unfortunately, dye-sensitized photoelectric conversion devices have the following problem: the absorption wavelengths of sensitizing dyes are limited compared to that of silicon, and therefore, the light utilization efficiency thereof is low, which results in a low photoelectric conversion efficiency of the devices.
Methods for solving the aforementioned problem have been studied, such as the use of a co-adsorbent in addition to a sensitizing dye (Patent Literature 1). This has been studied with the aim of suppressing aggregation/agglomeration of sensitizing dye particles when the sensitizing dye is adsorbed (fixed) onto a carrier such as an oxide semiconductor.